Median of the following discrete data is:
\[
1,2,2,3,3,3,4,4,4,4,5,5,5,5,5,......,10,10,10,10,10,10,10,10,10,10
\]
Show Hint
For patterned discrete data:
- First identify the repetition pattern.
- Find total observations.
- Locate the middle observation using cumulative frequencies.
- The value containing that middle position is the median.
Concept:
For discrete data arranged in ascending order:
\[
{Median = Middle Observation}
\]
If the total number of observations is odd:
\[
{Median}=\left(\frac{n+1}{2}\right)^{th} { observation}
\]
The pattern here shows:
\[
1 { occurs once}
\]
\[
2 { occurs twice}
\]
\[
3 { occurs three times}
\]
and so on up to
\[
10 { occurs ten times}
\]
Thus each number appears as many times as its own value.
Step 1: Find total number of observations.
Total observations:
\[
1+2+3+4+5+6+7+8+9+10
\]
Using sum of first \(n\) natural numbers:
\[
\frac{n(n+1)}{2}
\]
\[
=\frac{10(11)}{2}
\]
\[
=55
\]
Thus,
\[
n=55
\]
Step 2: Find the median position.
Since \(n\) is odd:
\[
{Median position}=\frac{55+1}{2}
\]
\[
=28^{th}{ observation}
\]
Step 3: Locate the 28th observation using cumulative frequencies.
\[
1 \rightarrow 1
\]
\[
2 \rightarrow 1+2=3
\]
\[
3 \rightarrow 3+3=6
\]
\[
4 \rightarrow 6+4=10
\]
\[
5 \rightarrow 10+5=15
\]
\[
6 \rightarrow 15+6=21
\]
\[
7 \rightarrow 21+7=28
\]
Thus the
\[
28^{th}
\]
observation is
\[
7
\]